ABSTRACT
Product components should be shaped to reflect their function and to prevent misconnection or misuse. Product developers can make a control a familiar shape to produce a useful association. Many examples of shape-coding are found in airplane cockpits. The tip of another control is shaped like a flap to create an association with raising and lowering the wing flap. This shape-coding can help a pilot select the correct control by means of visual inspection, feel, or both. Directional shapes can communicate purpose as well. An “Up” button in the form of an upward-pointing arrow, as opposed to an arrow graphic on a square button, just might help someone avoid pressing the “Down” button by mistake, such as when operating a forklift. If a tube and its associated connector port lack unique shape-coding, there is potential for someone to connect mismatching components. Pen-injectors are used by laypersons and clinicians alike to deliver all kinds of medications, including insulin and growth hormones.
